Speaking to GQ, Reeves explained that Bill and Ted's band Wyld Stallyns are yet to write the song that will change the world.

Reeves said: "One of the plot points is that these two people have been crushed by the responsibility of having to write the greatest song ever written and to change the world.

"And they haven't done it. So everybody is kind of like, 'Where is the song?' The guys have just drifted off into esoterica and lost their rock.

"And we go on this expedition, go into the future to find out if we wrote the song, and one future 'us' refuses to tell us, and another future 'us' blames us for their lives because we didn't write the song, so they're living this terrible life.

"In one version we're in jail; in another we're at some kind of highway motel and they hate us."

Galaxy Quest helmer Dean Parisot was recently revealed as the director for the movie, which has been written by original creators Ed Solomon and Chris Matheson.